LP #1592608: Large BLOB/TEXT/BINARY Produces NULL Checksum

**Reported in Launchpad by Jervin R last update 16-08-2016 09:14:45

When checksumming columns with large BLOB/TEXT/BINARY, this can cause CONCAT_WS to overflow and result in NULL value for this_crc/master_crc. By wrapping these columns into CRC32, it removes this problem.

Submitted a pull request for pt-table-sync here:

https://github.com/percona/percona-toolkit/pull/91

pt-table-checksum is affected as well.